1. Technical Field
The present invention relates to a covering of an opening of a building, and more particularly to a window blind with safety slats.
2. Description of Related Art
FIG. 1 shows a conventional window blind 1, including a headrail 10, a bottom rail 12, a plurality of slats 14, and a transmission unit 16. The slats 14 are parallel, and are arranged between the headrail 10 and the bottom rail 12. Each slat 14 has two elongated bores 142. Each bore 142 has curved opposite ends. The transmission unit 16 has two lifting control devices 18 and two cords 20. The lifting control devices 18 are received in the headrail 10. Each cord 20 has a control section 202 and a lift section 204. The control section 202 connects to the lift section 204. The lift sections 204 run over the lifting control devices 18, then pass through the bores 142 of the slats 14 in sequence, and finally are fastened to the bottom rail 12. The control sections 202 extend out of the headrail 10 to be operated by user. Pulling or releasing the control sections 202 may lift or lower the bottom rail 12 to retract or extend the slats 14.
When the bottom rail 12 is lowered to the lowest position, it has a risk to let a kid be strangled in case he/she pulls the lift sections 204 between the slats 14 out, and get the lift sections 204 around his/her neck (seeing FIG. 2). It is because that the lift sections 204 are free to move in the bores 142, so that the kid may pull them out easily and cause a tragedy.